
/* Copyright (c) Mark J. Kilgard, 1994. */

/* This program is freely distributable without licensing fees
   and is provided without guarantee or warrantee expressed or
   implied. This program is -not- in the public domain. */

#include <string.h>
#include <stdio.h>
#include <stdarg.h>
#include <GL/glut.h>

void
bitmap_output(int x, int y, char *string, void *font)
{
	int len, i;

	glRasterPos2f(x, y);
	len = (int) strlen(string);
	for (i = 0; i < len; i++) {
		glutBitmapCharacter(font, string[i]);
	}
}

void
stroke_output(GLfloat x, GLfloat y, char *format,...)
{
	va_list args;
	char buffer[200], *p;

	va_start(args, format);
	vsprintf(buffer, format, args);
	va_end(args);
	glPushMatrix();
	glTranslatef(x, y, 0);
	glScalef(0.005, 0.005, 0.005);
	for (p = buffer; *p; p++)
		glutStrokeCharacter(GLUT_STROKE_ROMAN, *p);
	glPopMatrix();
}

void
display(void)
{
	glClear(GL_COLOR_BUFFER_BIT);
	bitmap_output(40, 35, "This is written in a GLUT bitmap font.",
	              GLUT_BITMAP_TIMES_ROMAN_24);
	bitmap_output(30, 210, "More bitmap text is a fixed 9 by 15 font.",
	              GLUT_BITMAP_9_BY_15);
	bitmap_output(70, 240, "                Helvetica is yet another bitmap font.",
	              GLUT_BITMAP_HELVETICA_18);
	glMatrixMode(GL_PROJECTION);
	glPushMatrix();
	glLoadIdentity();
	gluPerspective(40.0, 1.0, 0.1, 20.0);
	glMatrixMode(GL_MODELVIEW);
	glPushMatrix();
	gluLookAt(0.0, 0.0, 4.0,  /* eye is at (0,0,30) */
	          0.0, 0.0, 0.0,      /* center is at (0,0,0) */
	          0.0, 1.0, 0.);      /* up is in postivie Y direction */
	glPushMatrix();
	glTranslatef(0, 0, -4);
	glRotatef(50, 0, 1, 0);
	stroke_output(-2.5, 1.1, "  This is written in a");
	stroke_output(-2.5, 0, " GLUT stroke font.");
	stroke_output(-2.5, -1.1, "using 3D perspective.");
	glPopMatrix();
	glMatrixMode(GL_MODELVIEW);
	glPopMatrix();
	glMatrixMode(GL_PROJECTION);
	glPopMatrix();
	glMatrixMode(GL_MODELVIEW);
	glFlush();
}

void
reshape(int w, int h)
{
	glViewport(0, 0, w, h);
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	gluOrtho2D(0, w, 0, h);
	glScalef(1, -1, 1);
	glTranslatef(0, -h, 0);
	glMatrixMode(GL_MODELVIEW);
}

int
main(int argc, char **argv)
{
	glutInit(&argc, argv);
	glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
	glutInitWindowSize(465, 250);
	glutCreateWindow("GLUT bitmap & stroke font example");
	glClearColor(1.0, 1.0, 1.0, 1.0);
	glColor3f(0, 0, 0);
	glLineWidth(3.0);
	glutDisplayFunc(display);
	glutReshapeFunc(reshape);
	glutMainLoop();
	return 0;             /* ANSI C requires main to return int. */
}
